Despite starring Keira Knightley and Sienna Miller, The Edge Of Love bombed with the sell-out opening-night audience at the Edinburgh International Film Festival.

The audience vote is believed to have been so bad the organisers of the festival took the unprecedented decision not to release the scores for any of the movies at the event this year.

But insiders have told Scotland on Sunday the film was in last place at one point and is still lurking well outside the top 10.

Although The Edge Of Love, a drama about Dylan Thomas's love life, has received generally favourable reviews from the critics, the audience at the gala performance were more difficult to please, with many simply judging the movie "boring".

Audiences at the festival are asked to judge all first-night performances on a scale of one to four.

The highest-scoring movie wins The Standard Life Audience Award, which has proven a springboard to success for several films in the past, including global hits such as Billy Elliot and Buena Vista Social Club.

The distributors of The Full Monty only realised they might have a major hit on their hands when it won the award in 1997. They rethought their release plans and it became the highest-grossing British film of all time.

But it is understood The Edge Of Love – written by Knightley's mother, Scottish playwright Sharman Macdonald – scored mostly ones and twos, despite the presence of stars Knightley and Miller.

Catriona Boyce, an 18-year-old Edinburgh student who was at one of the opening-night screenings at Edinburgh's Cineworld complex, said: "I'm not surprised. I didn't think it was particularly audience-orientated.

"None of the characters were sympathetic. At the end of the film a few people clapped, but it was really quite minimal."

One viewer, who gave the film only one out of four, said she thought Knightley's accent was inconsistent and the characters were unsympathetic, but that the main problem was simply the film was "boring".

After refusing to give out scores for the movies, the festival issued a top 10 last week which did not feature The Edge Of Love. There are 21 films in contention, but at that point several films were still to have their premieres.

Audiences much preferred Stone Of Destiny, a period drama about the 'liberation' of the famous Scottish coronation stone from Westminster Abbey by nationalist students, even though it was panned by critics.

They also got more enjoyment out of Standard Operating Procedure, a documentary about the atrocities at Abu Ghraib prison in Iraq; and Summer, a downbeat drama in which Robert Carlyle nurses a dying pal.

Asked if the low score was embarrassing for the festival, spokeswoman Clea Tammes said: "The Audience Award is always a law unto itself… This award is so unpredictable, that's why it's so exciting right up until the last minute."

In the film, Knightley plays a childhood friend and sometime lover of Thomas.

Miller plays Thomas's wife, who has a string of adulterous relationships. Matthew Rhys portrays the poet as a drunken, irresponsible womaniser.

The film's director John Maybury said The Edge Of Love had previously been turned down for a slot at Cannes.

Despite the audience's cool response to the opening film, the festival itself appears to have been a major hit.

Organisers had anticipated a fall in ticket sales this year while the event established itself in its new slot, but the number of tickets sold is up by 3% and box-office income is up by 5%.

The festival's managing director Ginnie Atkinson described the results as "fantastic" and confirmed the festival will stick with the June dates next year.

Standard Life Audience Award: Top 10

1 – Man On Wire, documentary about high-wire walker

2 - Standard Operating Procedure, Abu Ghraib documentary

3 - Elite Squad, Brazilian police drama

4 - Summer, downbeat drama with Robert Carlyle

5 - Somers Town, drama about two young friends in London

6 - A Complete History Of My Sexual Failures, film-maker interviews ex-girlfriends

7 - Stone Of Destiny, Scottish true-story drama

8 - Miss Pettigrew Lives For A Day, British comedy

9 - Dummy, offbeat British drama

10 - Before The Rains, drama set in colonial India

NOTE: This is the list as compiled on Friday and based on 18 out of 21 movies shown so far. It does not yet include Faintheart, Transsiberian, or WALL.E, all of which are likely to enter the top 10. The winner is due to be announced this afternoon.